I've installed Wolff spring kits in every S&W revolver I've ever owned except for the two M27's I've had. That has to have been at least 6 or 8 revolvers over the last 30 years and I've never had a problem with light primer strikes or trigger rebound. Of course I polish up the internal parts and clean and lube everything and I keep my guns clean. If you're inclined not to clean or lube your guns then maybe you'd need a heavier rebound spring but if you slick em' up you can get by with a lighter spring without problems.
Right now I've got the 8# hammer spring and the 13# rebound spring in my 642 and it seems to be working just fine.
I'm going to load up some ammo tomorrow and then maybe I can get out this weekend to really ring it out a bit but I really don't see anything taking place except for a lot of shooting.

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S&W M642-2,
ATI 1911a1, 4.25"